Justification:
The species overall is widespread and numerous, and present in many protected areas throughout its range. However, recent population estimates suggest that the future prospect of some subpopulations or subspecies is of some concern, particularly that of the Eastern White-bearded Wildebeest (which, it seems, may have undergone a precipitous decline in numbers). Furthermore, several subpopulations remain entirely dependent on management regimes, particularly the migratory wildebeest population of the Serengeti-Mara ecosystem, which accounts for some 70% of total population numbers.

The Common Wildebeest (Connochaetes taurinus) is formerly distributed from southern Kenya southwards to northern and eastern Namibia, Botswana, the Orange River in South Africa, and Mozambique (East 1999, Estes 2013). This species have also been introduced to regions outside their former distribution range, such as the Eastern Highlands of Zimbabwe and private farmland in Namibia (East 1999).

The ranges of the five subspecies are as follows (following East 1999, Estes 2013):

C. t. taurinus (Blue Wildebeest). Namibia and South Africa to Mozambique north of the Orange River, and from Mozambique to Zambia south of the Zambezi River, and from south-west Zambia to south-east and southern Angola.C. t. cooksoni (Cookson’s Wildebeest). Restricted to the Luangwa Valley, Zambia. May have ranged as vagrants onto the adjacent plateau into central Malawi. C. t. johnstoni (Nyassa or Johnston’s Wildebeest). North of Zambezi River in Mozambique to east-central Tanzania, and formerly in southern Malawi, where now extinct. C. t. albojubatus (Eastern White-bearded Wildebeest). Northern Tanzania to central Kenya just south of the Equator, west to the Gregory Rift Valley.C. t. mearnsi (Western White-bearded Wildebeest of the Serengeti ecosystem). Northern Tanzania and southern Kenya west of the Gregory Rift Valley, reaching Lake Victoria at Speke Bay.

During the late 1990s, estimates were available for all of the major surviving populations of this species, mainly from aerial surveys, producing a total population in excess of 1,200,000 (correcting for undercounting bias in aerial surveys). The migratory Serengeti-Mara population represented about 70% of global species numbers (942,000, having dropped below one million following the severe 1993 drought). Other population estimates were: Blue Wildebeest, 150,000 (with about half in protected areas, and one-quarter on private land and conservancies); Cookson’s Wildebeest, 16,000 (about 60% in protected areas); Nyassa Wildebeest, 96,000 (about two-thirds in protected areas, particularly Selous); and Eastern White-bearded Wildebeest, 94,000 (with about two-thirds in and around protected areas) (East 1999).

The most recent estimate of the total population size of Common Wildebeest is around 1,550,000 (Estes and East 2009), largely due to the rebounding of the Serengeti population to about 1,300,000 (Thirgood et al. 2004); other subspecies populations are estimated at 130,000 Blue Wildebeest, 5,000-10,000 Cookson’s, and 50,000-75,000 Nyassa. However, estimates of Eastern White-bearded Wildebeest indicate a steep decline in the subspecies’ populations to a current level of perhaps 6,000-8,000 animals.

Citing various authors, East (1999) indicates that population densities estimated by aerial surveys range from less than 0.15/km² in areas such as Kafue, Etosha, Hwange and the central and southern Kalahari, to 0.6-1.3/km² in areas such as Kruger, North Luangwa, Selous and Kajiado, and 3.6/km² in Tarangire. Recent total counts in areas where the species is abundant have produced population density estimates as high as 34.0-35.0/km², e.g., Serengeti and Ngorongoro Crater.

This species occurs in short-grass plains, and bordering Acacia savanna open bushland and woodland in drier areas. Serengeti wildebeests thrive on short grasslands on alkaline and volcanic soils during the rainy season, and withdraw to longer grasslands in areas of higher rainfall and permanent water during the dry season. They are rarely found above 1,800-2,100 m (e.g., the Ngorongoro Crater). Common Wildebeest are pure grazers, requiring water at least every day or two in the dry season (Estes 2013).

Once often found in large concentrations, the numbers and distribution of Common Wildebeest have been reduced by the spread of settlement and livestock, elimination of water sources through watershed deforestation and expropriation for irrigation, poaching for meat, the loss of the seasonal ranges of some migratory populations, and game eradication programs in failed efforts to eliminate the wild hosts of sleeping sickness (nagana) and other diseases of domestic livestock (East 1999, Estes 2013). Fences that blocked migration between wet and dry-season ranges have caused mass die-off events, by denying access to water and to higher-rainfall refuges during severe droughts. A notorious example is the decline in numbers and episodes of mass mortality of Botswana wildebeest caused by veterinary cordon fences that blocked drought-induced migrations, particularly after thousands died at Lake Xau in the north-east of the Kalahari Desert in 1980 (Owens and Owens 1980).

The vulnerability of this species to illegal hunting and loss of habitat caused by the encroachment of settlement is increased by the dependence of some migratory populations on seasonal access to unprotected rangelands. In these cases (e.g., Liuwa Plain, Tarangire and Kajiado) effective protection and management of national parks which contain only part of the population’s annual range may be insufficient to prevent major population declines. Loss of range outside protected areas may result in the replacement of migratory populations with much smaller (but nevertheless substantial) resident populations within protected areas, as has occurred in areas such as Etosha National Park and Central Kgalagadi Game Reserve. Some wildebeest populations are naturally relatively sedentary and/or their seasonal movements are generally accommodated within protected areas (e.g., Kafue, Luangwa, Hwange and Selous). The overall status of the species may not change in the long term if it continues to be well represented in protected areas and on private land, but if current trends continue its populations will become increasingly sedentary within fenced parks, reserves and farms (East 1999).

The future of the enormous migratory wildebeest population of the Serengeti-Mara ecosystem will have a major impact on the species’ overall conservation status. This population has shown signs of recovery from its decline in the early 1990s (Thirgood et al. 2004), but two sections of the migration route – the Ikoma Open Area and the Mara Group Ranches – currently receive limited protection and are threatened by poaching or agriculture. Other smaller, but substantial populations, of Common Wildebeest occur in areas such as: Kafue and Liuwa Plain (Zambia), Etosha (Namibia), Okavango, Makgadikgadi-Nxai Pan, Ngamiland and the central and southern Kalahari (Botswana), Hwange (Zimbabwe), Kruger, Hluhluwe-Umfolozi and Mkuzi (South Africa), Hlane (Swaziland) and private farmland (Namibia, Botswana, Zimbabwe and South Africa) (Blue Wildebeest); the Luangwa Valley (Zambia) (Cookson’s Wildebeest); the Selous ecosystem (Tanzania) (Nyassa Wildebeest); Ngorongoro Crater (Tanzania) (Western White-bearded Wildebeest); and Tarangire (Tanzania) and Kajiado (Kenya) (Eastern White-bearded Wildebeest). Most of these populations are currently stable or increasing. Some populations have decreased substantially from historical levels because of the loss of their former migration routes (e.g., Etosha, Kalahari).